Ibuprofen, the generic name for 2-(4-isobutylphenyl)propionic acid, is a well known anti-inflammatory drug and is disclosed in U.S. Pat. Nos. 3,228,831 and 3,385,886. Normally, ibuprofen is formulated for sale to the consumer in the form of compressed tablets or capsules.
Previously known compositions produced by a wet granulation method have required relatively large percentages of excipients to produce a compressible formulation. This lowers the maximum level of ibuprofen that can be contained in the formulation. This in turn increases the size of the tablet formed from such a formulation, especially a problem for the higher dose level tablets, such as 800 or 1200 mg units. This increased size is undesirable both from a manufacturing and handling standpoint and a patient acceptability standpoint. There has been a need, therefore, for higher active ingredient levels in compressible formulations.
U.S. Pat. No. 4,609,675 discloses a method of preparing a pharmaceutical ibuprofen-containing granulate composition suitable for preparing tablets of relatively high dosage. This is accomplished by dry mixing ibuprofen with 1 to 15 percent by weight croscarmellose sodium NF (cross-linked sodium carboxymethylcellulose). This dry granulation method meets this need described above, but uses a relatively expensive additive to accomplish it. Croscarmellose sodium NF is used at levels up to 15 percent, preferably about 7 to 8 percent. This contributes significantly to the cost of the formulation.
It is an object of the present invention to provide an ibuprofen granulation formulation having a high level of active ingredient and which can be ultimately tabletized by direct compression.
It is a further object of the present invention to provide an ibuprofen granulation that can be formulated with additional excipients, and, optionally other active ingredients, and compressed into tablets having high hardness, short disintegration time, and fast dissolution rate without being unacceptably friable.
It is a still further object of the invention to provide a wet granulation method that produces a granulation formulation having a high ibuprofen content.